Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / clr / src / BCL / System / Security / Cryptography / SymmetricAlgorithm.cs / 1305376 / SymmetricAlgorithm.cs
using System.Diagnostics.Contracts; // ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== //[....] // // // SymmetricAlgorithm.cs // namespace System.Security.Cryptography { [System.Runtime.InteropServices.ComVisible(true)] public abstract class SymmetricAlgorithm : IDisposable { protected int BlockSizeValue; protected int FeedbackSizeValue; protected byte[] IVValue; protected byte[] KeyValue; protected KeySizes[] LegalBlockSizesValue; protected KeySizes[] LegalKeySizesValue; protected int KeySizeValue; protected CipherMode ModeValue; protected PaddingMode PaddingValue; // // protected constructors // protected SymmetricAlgorithm() { // Default to cipher block chaining (CipherMode.CBC) and // PKCS-style padding (pad n bytes with value n) ModeValue = CipherMode.CBC; PaddingValue = PaddingMode.PKCS7; } // SymmetricAlgorithm implements IDisposable // To keep mscorlib compatibility with Orcas, CoreCLR's SymmetricAlgorithm has an explicit IDisposable // implementation. Post-Orcas the desktop has an implicit IDispoable implementation. #if FEATURE_CORECLR void IDisposable.Dispose() #if false { } #endif // false #else [System.Security.SecuritySafeCritical] // auto-generated public void Dispose() #endif // FEATURE_CORECLR { Dispose(true); GC.SuppressFinalize(this); } public void Clear() { (this as IDisposable).Dispose(); } protected virtual void Dispose(bool disposing) { if (disposing) { // Note: we always want to zeroize the sensitive key material if (KeyValue != null) { Array.Clear(KeyValue, 0, KeyValue.Length); KeyValue = null; } if (IVValue != null) { Array.Clear(IVValue, 0, IVValue.Length); IVValue = null; } } } // // public properties // public virtual int BlockSize { get { return BlockSizeValue; } set { int i; int j; for (i=0; iBlockSizeValue || (value % 8) != 0) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidFeedbackSize")); FeedbackSizeValue = value; } } public virtual byte[] IV { get { if (IVValue == null) GenerateIV(); return (byte[]) IVValue.Clone(); } set { if (value == null) throw new ArgumentNullException("value"); Contract.EndContractBlock(); if (value.Length != BlockSizeValue / 8) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidIVSize")); IVValue = (byte[]) value.Clone(); } } public virtual byte[] Key { get { if (KeyValue == null) GenerateKey(); return (byte[]) KeyValue.Clone(); } set { if (value == null) throw new ArgumentNullException("value"); Contract.EndContractBlock(); if (!ValidKeySize(value.Length * 8)) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidKeySize")); // must convert bytes to bits KeyValue = (byte[]) value.Clone(); KeySizeValue = value.Length * 8; } } public virtual KeySizes[] LegalBlockSizes { get { return (KeySizes[]) LegalBlockSizesValue.Clone(); } } public virtual KeySizes[] LegalKeySizes { get { return (KeySizes[]) LegalKeySizesValue.Clone(); } } public virtual int KeySize { get { return KeySizeValue; } set { if (!ValidKeySize(value)) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidKeySize")); KeySizeValue = value; KeyValue = null; } } public virtual CipherMode Mode { get { return ModeValue; } set { if ((value < CipherMode.CBC) || (CipherMode.CFB < value)) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidCipherMode")); ModeValue = value; } } public virtual PaddingMode Padding { get { return PaddingValue; } set { if ((value < PaddingMode.None) || (PaddingMode.ISO10126 < value)) throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidPaddingMode")); PaddingValue = value; } } // // public methods // // The following method takes a bit length input and returns whether that length is a valid size // according to LegalKeySizes public bool ValidKeySize(int bitLength) { KeySizes[] validSizes = this.LegalKeySizes; int i,j; if (validSizes == null) return false; for (i=0; i< validSizes.Length; i++) { if (validSizes[i].SkipSize == 0) { if (validSizes[i].MinSize == bitLength) { // assume MinSize = MaxSize return true; } } else { for (j = validSizes[i].MinSize; j<= validSizes[i].MaxSize; j += validSizes[i].SkipSize) { if (j == bitLength) { return true; } } } } return false; } [System.Security.SecuritySafeCritical] // auto-generated static public SymmetricAlgorithm Create() { // use the crypto config system to return an instance of // the default SymmetricAlgorithm on this machine return Create("System.Security.Cryptography.SymmetricAlgorithm"); } [System.Security.SecuritySafeCritical] // auto-generated static public SymmetricAlgorithm Create(String algName) { return (SymmetricAlgorithm) CryptoConfig.CreateFromName(algName); } public virtual ICryptoTransform CreateEncryptor() { return CreateEncryptor(Key, IV); } public abstract ICryptoTransform CreateEncryptor(byte[] rgbKey, byte[] rgbIV); public virtual ICryptoTransform CreateDecryptor() { return CreateDecryptor(Key, IV); } public abstract ICryptoTransform CreateDecryptor(byte[] rgbKey, byte[] rgbIV); public abstract void GenerateKey(); public abstract void GenerateIV(); } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- DataGridViewTextBoxCell.cs
- SqlUdtInfo.cs
- _StreamFramer.cs
- EventDescriptorCollection.cs
- SoapFault.cs
- LinearKeyFrames.cs
- EventRecordWrittenEventArgs.cs
- KnownTypesProvider.cs
- SizeConverter.cs
- Queue.cs
- TransportElement.cs
- ManagementInstaller.cs
- counter.cs
- SID.cs
- SqlBuilder.cs
- AttachedPropertyMethodSelector.cs
- MethodBody.cs
- WebDescriptionAttribute.cs
- EventLogEntryCollection.cs
- WebPartEventArgs.cs
- FutureFactory.cs
- iisPickupDirectory.cs
- bidPrivateBase.cs
- RoutedEventValueSerializer.cs
- HtmlTableCell.cs
- HeaderCollection.cs
- FileRecordSequence.cs
- PrintPageEvent.cs
- XslTransformFileEditor.cs
- RTLAwareMessageBox.cs
- SmiRecordBuffer.cs
- ImageSource.cs
- Help.cs
- OdbcDataAdapter.cs
- DesignerWebPartChrome.cs
- StaticSiteMapProvider.cs
- _ListenerResponseStream.cs
- InternalEnumValidator.cs
- ConfigXmlElement.cs
- ExtensionFile.cs
- BevelBitmapEffect.cs
- RadioButtonPopupAdapter.cs
- AutoGeneratedFieldProperties.cs
- PictureBoxDesigner.cs
- CounterNameConverter.cs
- PasswordPropertyTextAttribute.cs
- HwndKeyboardInputProvider.cs
- BuildProvider.cs
- JoinSymbol.cs
- Events.cs
- StackSpiller.Temps.cs
- DragDropManager.cs
- HtmlDocument.cs
- MustUnderstandSoapException.cs
- UnmanagedMemoryStreamWrapper.cs
- SQLSingleStorage.cs
- CodeTypeConstructor.cs
- ClientSettingsStore.cs
- CacheManager.cs
- MimeTypePropertyAttribute.cs
- StatusBarItemAutomationPeer.cs
- KnownTypes.cs
- ConfigurationStrings.cs
- DataServiceProviderWrapper.cs
- BindingGraph.cs
- FileInfo.cs
- ApplicationInfo.cs
- FormViewAutoFormat.cs
- XmlSchemaIdentityConstraint.cs
- MsmqPoisonMessageException.cs
- Context.cs
- CalloutQueueItem.cs
- PersonalizableTypeEntry.cs
- UnsafeNativeMethods.cs
- WebPartConnectionsConnectVerb.cs
- Thread.cs
- TypeLibConverter.cs
- TextBoxAutomationPeer.cs
- C14NUtil.cs
- WebPartHeaderCloseVerb.cs
- PersonalizationProviderHelper.cs
- IndexerNameAttribute.cs
- XmlUtf8RawTextWriter.cs
- XmlSchemaComplexContentRestriction.cs
- VirtualPathUtility.cs
- PathFigureCollectionValueSerializer.cs
- DetailsViewUpdateEventArgs.cs
- DataRelation.cs
- FullTextLine.cs
- BooleanConverter.cs
- ListBoxItemWrapperAutomationPeer.cs
- GridItem.cs
- WebPartEditVerb.cs
- AnnotationResource.cs
- OdbcRowUpdatingEvent.cs
- ThemeInfoAttribute.cs
- IisTraceListener.cs
- ExecutionContext.cs
- MappingItemCollection.cs
- SQLMoneyStorage.cs